Merge "Issue 186618:run cts com.android.cts.appsecurity.DocumentsTest--testTree--fail5.1_r5 [root cause]in testTree method, the second writeFully(...) task may be executed in the AsyncTask after readFully(...) task, or they may be executed at the same time. Since the read and write operation is not protected by synchronized. Two tasks running on different thread my access doc.contents at the same time, and may lead to a null pointer crash [changesY] using AsyncTask.SERIAL_EXECUTOR instead of AsyncTask.THREAD_POOL_EXECUTOR" into lollipop-cts-dev am: d66ed5124d
am: d33d431c81
* commit 'd33d431c81f06676e047f62b76ffe5f430f7bb0b':
Issue 186618:run cts com.android.cts.appsecurity.DocumentsTest--testTree--fail5.1_r5 [root cause]in testTree method, the second writeFully(...) task may be executed in the AsyncTask after readFully(...) task, or they may be executed at the same time. Since the read and write operation is not protected by synchronized. Two tasks running on different thread my access doc.contents at the same time, and may lead to a null pointer crash [changesY] using AsyncTask.SERIAL_EXECUTOR instead of AsyncTask.THREAD_POOL_EXECUTOR